<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>

<body>
    <div id="example">
       <input type="text" v-model.lazy="message"></input>
        {{tip}}
    </div>

    <script src="../../js/vue.js"></script>
    <script>
        var vm = new Vue({
            el: '#example',
            data: {
                message: 'Hello',
                tip: ""
            },
            watch: {
                message:function(){
                    this.tip = "数据message改变，侦听器被触发了，"
                }
            }
        })
    </script>
</body>

</html>